Symphyocladia marchantioides (Harv.) Falkenb.

Scientific Description

Habit and structure. Thallus brown-red, 1–2 cm long and 2–4 mmbroad, prostrate with a main branch bearing occasional to frequent similar but shorter and slenderer marginal branches. Attachment by rhizoids from basal parts; epilithic or epiphytic. Structure. Growth from apical cells 6–10 µm in diameter which divide transversely, the subapical cells cutting off 6 or 8 pericentral cells, 3 or 4 on each side, without transverse subdivision of these cells; thallus usually 2(–3) cells thick; apical cells and derivative segments remain laterally attached congenitally, with the axial cells branching laterally 2–5 cells apart; mature pericentral cells 90–120 µm long, the lateral (outer) ones 25–45 µm in diameter, the transverse ones 15–20 µm in diameter. Rhizoids unicellular, cut off from pericentral cells, with multicellular haptera. Trichoblasts arising from dormant apical cells on margins of branches, branched, becoming 600–1000 µm long, lower cells 20–30 µm in diameter. Cells uninucleate; rhodoplasts discoid.

Reproduction. Gametophytes not seen in the only southern Australian collection. Tetrasporangia borne in laterally fused stichidia, in straight rows, one per segment, 60–90 µm in diameter.

Distribution. In southern Australia, known from Edithburg, S. Aust., to Point Hicks E Vic., and from eastern Australia. New Zealand, N of Banks Pen; western Pacific Ocean; Azores; eastern and western Australia; South Africa; Japan.

[After Womersley, Mar. Benthic Fl. Southern Australia IIID: 341 (2003)]